Direct peroxide-peroxide fuel cell - Part 1: The anode and cathode catalyst of carbon fiber cloth supported dendritic Pd

Dendritic Pd is electrodeposited uniformly on carbon fiber cloth via a potential pulse technique. The electrode is characterized by scanning electron microscopy, transmission electron microscopy and X-ray diffractometer, and it shows a unique open structure allowing the full utilization of Pd surface active sites. H2O2 electrooxidation in KOH solution and electroreduction in H2SO4 solution on the dendritic Pd electrode are studied by linear sweep voltammetry and chronoamperometry. The electrode exhibits a high catalytic performance for both H2O2 electrooxidation and electroreduction, and it outperforms the conventional electrode made with commercial Pd/C powder. KOH and H2SO4 in excess show no improvement to the activity of H2O2 oxidation and reduction, respectively. The overpotential at the same current density for H2O2 electrooxidation in alkaline solution is significantly lower than that for electroreduction in acid medium on the dendritic Pd electrode. (C) 2012 Elsevier B.V. All rights reserved.